All are heritage tram routes, as they use vintage tramcars exclusively, and should not be confused with the modern Porto Metro light rail system.

The last mule-drawn car was retired in 1904, and electrification was complete with the elimination of urban steam engines in 1914.

In 1946, the city purchased the tram system from CCFP and took over its operation, with a new municipal company, Serviço de Transportes Colectivos do Porto (STCP).

The 1960s and the 1970s were marked by a continuous dismantling of tram tracks and a preference for cheaper bus transport.

[3]: 46  On 11 June 1996, the final route, 18, was downgraded from a full-service tram line to a heritage service with reduced frequency, but operating seven days a week.

[4] Route 18's 4 km section along Avenida Boavista was later closed, but tram service was gradually re-introduced in the 2000s on other sections, in the form of additional heritage-tram services, lines 1 and 22, as well as the former Line T (the Porto Tram City Tour, which has since been discontinued).

Tram fares are paid with a customized ticket that can be bought on board of the vehicle, at the Museum or in some hotels.